I’d like to optimize my theme for my use using a given font and weight, and I was wondering if there’s a way to set the CSS cascade to simply fall through to the font the user chose in the Settings panel?

For example, I have this for .entity.name.tag:

font-family: 'SourceCodePro-Semibold', monospace;

Which works perfectly if you have Source Code Pro installed, but if you don’t you get the system Monospace.

IIRC, the font setting is done via code, i.e. there is code that reads the settings and then that code pokes the font into the generated HTML.

So what you can do? I’m not sure. Maybe tell CSS to set the xyzzy font if Source Code Pro is not installed, and then add code that replaces the xyzzy font with the settings font, wherever set? I haven’t tried this though. I’m kind of afraid horrible things will happen for people who don’t have the xyzzy font installed (which would be most people).